1. INDICATIONS

Diagnostic

• Suspected SBP (spontaneous bacterial peritonitis)

• New-onset ascites

• Worsening liver failure

• Abdominal pain or fever with ascites

Therapeutic

• Large-volume ascites causing:

  • Respiratory compromise

  • Abdominal pain

  • Early satiety

  • Refractory ascites

2. CONTRAINDICATIONS 

• Severe coagulopathy

• Platelets < 20–30k

• INR > 2.5–3

• Severe abdominal wall infection

• Pregnancy (choose safe site)

Modern evidence: Paracentesis is VERY safe even with moderate INR elevation.

3. PRE-PROCEDURE CHECKLIST

Labs

• ✔ Platelets > 20k (lower acceptable for diagnostic tap)

• ✔ INR ideally < 2.5, but not mandatory

• ✔ CBC, CMP

• ✔ Lactate if infected

Ultrasound

• Identify pocket of ascitic fluid

• Avoid bowel loops

• Avoid engorged superficial vessels

• Choose left lower quadrant (LLQ) or right lower quadrant (RLQ), 2–3 cm below the umbilicus and lateral

Equipment

• Paracentesis kit (catheter-over-needle)

• Large drainage bottle or vacuum container

• 1% Lidocaine

• Chlorhexidine

• Sterile gloves and drapes

4. PRE-MEDICATION

Most patients do NOT require systemic sedation.

Local Anesthesia (standard)

• 1% Lidocaine: 5–10 mL SC + deeper tissues

• Additional 3–5 mL at peritoneum (patients often feel this layer sharply)

Light Sedation (optional)

Use ONLY if patient is anxious:

🚫 Avoid deep sedation → aspiration and hypotension risk in cirrhotics.

5. POSITIONING

• Supine or slightly reclined

• Head of bed 20–30°

• Expose abdomen, visualize with ultrasound

6. PROCEDURE STEPS (ULTRASOUND-GUIDED)

1. Time-out

• Confirm patient, procedure, side/site

2. Identify ideal site

• LLQ preferred: fewer vessels

• Avoid the inferior epigastric artery (use Doppler if available)

3. Sterile prep

• Chlorhexidine

• Wide sterile drape

4. Local anesthesia

• Create skin wheal

• Advance needle at 45°, inject lidocaine down to peritoneum

5. Insert introducer needle

• Direct needle perpendicular to skin or at slight downward angle

• When “pop” is felt → you are entering peritoneum

• Aspirate to confirm ascitic fluid return

6. Advance catheter

• Slide catheter off needle

• Remove needle

• Connect catheter to:

  • Vacuum bottle for therapeutic

  • Syringe + tubes for diagnostic samples

7. Drainage

• For large-volume paracentesis → drain up to 5–6 L safely

• Stop if:

  • Hypotension

  • Pain

  • Coughing

  • Vasovagal symptoms

8. Withdrawal + dressing

• Remove catheter

• Apply clean gauze and Tegaderm

7. POST-PROCEDURE

Diagnostic labs (ALWAYS for suspected SBP):

• Cell count with differential

• Gram stain & culture

• Total protein

• Albumin (for serum-ascites albumin gradient—SAAG)

• LDH

• Glucose

• Amylase (if pancreatic etiology suspected)

Albumin Replacement

For therapeutic paracentesis > 5 liters:

➡ Albumin 6–8 g per liter removed
(Example: remove 6 L → give 40–50 g albumin)

Monitor

• Vital signs (q15–30 mins)

• Watch for hypotension

• Assess for bleeding or continued leak

8. COMPLICATIONS

• Bleeding (rare)

• Bowel perforation (very rare with US guidance)

• Ascitic leak

• Hypotension

• Infection

• Renal dysfunction (in large-volume taps without albumin)

9. ICU PEARLS 

• Ultrasound ALWAYS

• LLQ = safest site

• Replace albumin for >5 L removal

• Do diagnostic paracentesis ASAP in any cirrhotic with fever, pain, GI bleed, AMS, or renal failure

• Avoid deep sedation

• Know that therapeutic paracentesis dramatically improves breathing in ICU ascites patients

• Always document volume removed + labs sent